Slide positioner

ABSTRACT

A slide positioner for moving a structural member from an inoperating position to a working or operating position has a square shaft for supporting the structural member. Two bearing assemblies are adapted for supporting the sliding shaft. The two bearing assemblies are spaced one from the other and are connected to a stationary base. One of the bearing assemblies is rigidly connected to a pneumatic cylinder whose piston rod is connected to the sliding shaft. The bearing assemblies are mountable to the base in various angular positions since the bearing assemblies may be pivoted around an axis which is parallel to the axis of the sliding shaft.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a slide positioner adapted tomove any structural member from an inoperating position to a working oroperating position.

[0003] 2. Description of the Related Art

[0004] A slide positioner known from a brochure of G.C. Westec Ltd.,Thunder Bay, Ontario, Canada, includes the various elements andfeatures. A sliding shaft supporting a structural member (e.g., aso-called threading pan) has a polygonal (namely a square) crosssection. A bearing device is adapted for supporting the sliding shaftand may be connected to a stationary frame. The bearing device is alsoconnected to a linear motor, typically a pneumatic cylinder whose pistonrod is connected to the sliding shaft. During the normal operation ofthe paper machine, the slide positioner holds the threading pan in aposition beside the machine. During startup or after a web break, thethreading pan is moved into an operating position and held there duringthe threading operation.

[0005] Additionally, the structural member to be moved may be a peelingor lifting nozzle (or separating blow pipe) which is used in apaper-making machine in order to peel off an edge strip (or “tail”) ofthe paper web produced, such as from a press roll or a drying cylinder.The structural member may also be a transfer device or a so-calledmini-doctor which is used to transfer the edge strip to a followingsection of the paper machine. All those structural members are helpfulto facilitate the threading of paper web into the machine when themachine is started up or after a web break.

SUMMARY OF THE INVENTION

[0006] Slide positioners of conventional design have proven successfulin operation. However, a number of demands have prompted the need toimprove the conventional design.

[0007] Those demands include the following objects:

[0008] A) Various mounting requirements, in particular on paper-makingor paper-finishing machines, shall be met while maintaining the abilityto accurately position the structural member in the machine in order toperform the desired task;

[0009] B) The manufacturing costs should be minimized by usinginterchangeable elements; and

[0010] C) Slide elements which are subject to wear due to frictionbetween the sliding shaft and the bearing assemblies should be easilyreplaceable.

[0011] In one embodiment of the present invention, the sliding shaftincludes two spaced bearing assemblies which are mountable relative to astationary base in various angular positions. In other words, eachbearing assembly is supported in a bore hole or in a circular cutout ofthe stationary base. As a result, the structural member supported by thesliding shaft can easily be brought into a convenient position (e.g.,relative to the paper machine). Thereafter, the bearing assemblies arefixed to the stationary base, e.g., with bolts. Therefore, the slidepositioner of the present invention, meets several different mountingrequirements, e.g., on a paper-making machine, allowing the structuralmember to be accurately positioned in the place where it will operate.

[0012] In a preferred embodiment of the invention, the rotational axisof the bearing assemblies coincides with the axis of the sliding shaft.In other words, when the structural member is adjusted into its requiredangular position, the bearing assemblies together with the sliding shaftand with the linear motor are pivoted around the axis of the slidingshaft. Since the cylinder, specifically the stationary element of thelinear motor, is connected to only one of the two bearing assemblies,the installation of linear motors of various stroke lengths is possible,without having to make any other changes to the slide positionerassembly.

[0013] According to another embodiment of the invention, the rotationalaxis of the bearing assemblies coincides with the axis of the linearmotor. This design allows the mounting of the linear motor (e.g.,pneumatic cylinder) directly onto the stationary base, so that the needfor flexible pressure lines is avoided.

[0014] According to another aspect of the invention, each of the bearingassemblies includes at each surface of the polygonal sliding shaft aseparate replaceable slide strip. Preferably, the sliding shaft has theform of a square tubing; in this case, each bearing assembly is fittedwith four identical, replaceable slide strips. These are preferablymanufactured from a self-lubricating material, e.g., PTFE(polytetraflouroethylene). This material reduces the friction forcesbetween the sliding shaft and the bearing assemblies. If, nevertheless,one of the slide strips becomes worn, this single slide strip may beeasily replaced, without having to disassemble the complete slidepositioner.

[0015] It should be noted that the aforementioned separately replaceableslide strips may be use not only in the above-described bearingassemblies which are mountable to the base in various angular positions.Rather than that, the separately replaceable slide strips may also beused in conventional slide positioners having at least one rigidlymounted bearing device for the sliding shaft.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above-mentioned and other features and advantages of thisinvention, and the manner of attaining them, will become more apparentand the invention will be better understood by reference to thefollowing description of embodiments of the invention taken inconjunction with the accompanying drawings, wherein:

[0017]FIG. 1 is a partial cut-away view of one embodiment of the presentinvention;

[0018]FIG. 2 is a cross sectional along section line 2 of FIG. 1;

[0019]FIG. 3 is a view along section line 3 of FIG. 1 onto thestationary base assembly, only;

[0020]FIG. 4 is a side view of one of the slide strips with its holder;

[0021]FIG. 5 is a view along section line V of FIG. 4; and

[0022]FIG. 6 is a partial cut-away view of another embodiment of a slidepositioner of the present invention.

[0023] Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplifications set out hereinillustrate at least one preferred embodiment of the invention, in oneform, and such exemplifications are not to be construed as limiting thescope of the invention in any manner.

DETAILED DESCRIPTION OF THE INVENTION

[0024] A slide positioner 8 shown in FIGS. 1-5 includes a sliding shaft10 supporting a structural member 9 and having a square cross section.Sliding shaft 10 is supported by a first bearing assembly 11 and by asecond bearing assembly 12 spaced from first bearing assembly 11.Bearing assemblies 11 and 12 are connected to a stationary base assembly20. As an example, base assembly 20 includes two identical flanges 21and 22 which are rigidly connected to a base plate 23. Each of flanges21, 22 has a circular cutout 24 which is arranged coaxial to slidingshaft 10.

[0025] Each of bearing assemblies 11, 12 has a hub 13, with hubs 13being identical. Each hub 13 is a cylindrical collar which fits intocylindrical cutout 24 of one of stationary flanges 21, 22. Also, eachhub 13 has a centrical square cutout which is somewhat larger than thecross section of sliding shaft 10. Therefore, at each of the foursurfaces of sliding shaft 10, a separate slide strip 15 is mountedbetween sliding shaft 10 and hub 13. Each slide strip 15 is connected tohub 13 by a holder 16 (FIGS. 4 and 5). It may be now understood thatslide positioner 8 includes eight identical slide strips 15 as well aseight identical holders 16. Between bearing assemblies 11, 12, a dustcover 14 is arranged. The same is divided into two parts so it may beeasily removed to inspect and/or replace one or more of slide strips 15.

[0026] Each of stationary flanges 21 and 22 has, around circular cutout24, two circular slots 25 which allow mounting of bearing assemblies 11and 12 (i.e., first bearing assembly 11 together with a support for alinear motor 29) in a selectable angular position, as shown at a, b andc, respectively, in FIG. 2. Selected position a, b, c will be fixed bytwo bolts 26 in each bearing assembly 11, 12. If linear motor 29 shouldbe mounted in a position e, d or f (at about 90° to vertical positiona), support 28 may be mounted by using additional bolt holes 27.

[0027] Linear motor 29 is formed as a pneumatic cylinder. Piston rod 30thereof is connected by a clevis 31 to an arm of a sleeve 32 which isfastened to sliding shaft 10. FIG. 1 shows only a support of structuralmember 9. By a supply of pressure to cylinder 29, member 9 can be movedfrom an inoperating position (shown in full lines) to an operatingposition shown in dot-dash-lines, with the strike length beingdesignated S. As shown in FIG. 6, structural member 9 may be, as anexample, a peeling jet pipe.

[0028] In FIG. 6, sliding shaft 10, linear motor 29 with piston rod 30connecting elements 31, 32, as well as replaceable slide strips 15 withholders 16, may be identical with the corresponding elements of FIGS. 1to 5. Base assembly 20A includes a base plate 23A and two supports 21Aand 22A, each having a circular collar being coaxial to linear motor 29.Linear motor 29 is connected to one support 21A. There are again twobearing assemblies 11A and 12A, each having a hub 13A which supportsslide strips 15. Each hub 13A has a flange having a circular cutout 24into which a collar of one of supports 21A, 22A is fits. Also, each hub13A has two circular slots 25 (similar to slots 25 of FIG. 3) whichallow the fastening of bearing assemblies 11A, 12A together with slidingshaft 10 in a selectable angular position around the axis of linearmotor 29.

[0029] While this invention has been described as having a preferreddesign, the present invention can be further modified within the spiritand scope of this disclosure. This application is therefore intended tocover any variations, uses, or adaptations of the invention using itsgeneral principles. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this invention pertains and which fallwithin the limits of the appended claims.

What is claimed is:
 1. A slide positioner for moving a structural memberfrom an inoperative position to at least one of an operative positionand a working position, said slide positioner comprising: a base; afirst bearing assembly connected to said base; a second bearing assemblyconnected to said base and spaced from said first bearing assembly; anda sliding shaft supported by said first bearing assembly and said secondbearing assembly, said sliding shaft being configured for supporting thestructural member, said sliding shaft having a shaft axis and an atleast approximately polygonal cross section, said first bearing assemblyand said second bearing assembly conjunctively defining a bearing axisand being one of pivotable and rotatable about said bearing axis, saidbearing axis being parallel to said shaft axis, said first bearingassembly and said second bearing assembly thereby being mountable invarious angular positions relative to said base.
 2. The slide positionerof claim 1, wherein said bearing axis coincides with said shaft axis. 3.The slide positioner of claim 2, further comprising a linear motor, saidlinear motor including a stationary element and a movable element, saidstationary element being rigidly connected to said first bearingassembly, said movable element being connected to shaft sliding shaft.4. The slide positioner of claim 3, wherein said movable element is apiston rod.
 5. The slide positioner of claim 1, further comprising alinear motor rigidly connected to said first bearing assembly, saidlinear motor having a motor axis, said motor axis coinciding with saidbearing axis.
 6. The slide positioner of claim 1, wherein said slidingshaft has a plurality of sliding surfaces, each of said first bearingassembly and said second bearing assembly having a separatelyreplaceable slide strip associated with and positioned relative to eachsliding surface.
 7. The slide positioner of claim 6, wherein eachseparately replaceable slide strip is composed of a self-lubricatingmaterial.
 8. A slide positioner for moving a structural member from aninoperative position to at least one of an operative position and aworking position, said slide positioner comprising: a base; at least onebearing assembly connected to said base; a sliding shaft supported bysaid at least one bearing assembly, said sliding shaft being configuredfor supporting the structural member, said sliding shaft having an atleast approximately polygonal cross section, said sliding shaft therebyhaving a plurality of sliding surfaces, at least one said bearingassembly having a separate replaceable slide strip associated with andpositioned relative to each sliding surface.
 9. The slide positioner ofclaim 8, wherein each separately replaceable slide strip is composed ofa self-lubricating material.